1. Field of the Invention
This invention relates generally to bag assemblies for upright vacuum cleaners, and more particularly, to a bag having an internal oscillator tube which vibrates the bag walls during use to dislodge dirt and prevent restrictions in air flow through the bag walls.
2. Description of the Prior Art
A vacuum cleaner removes dirt and other foreign material from a surface being cleaned and deposits them in a dirt collecting bag. The vacuum cleaner main housing carries a vacuum generating means referred to as a "motor-fan unit" which creates a flow of dirt laden air through the housing to the dirt collecting bag. The vacuum pressure generated in the main housing draws the dirt laden air through the housing and through an air duct into the dirt collecting bag which is attached by a mouth opening to the air duct.
The dirt collecting bag is formed of an air pervious material, such as cloth, and functions to filter all the dirt laden air and collect the dirt and dust within the bag. Filtered air passes through the bag side walls and is exhausted to the atmosphere. Due to the nature of the air flow through the housing and bag, dirt and dust particles tend to build up on the interior side walls of the bag. As dirt cakes the bag interior side walls, the porosity of the bag decreases and air flow is restricted. As the air flow through the bag gradually decreases, the vacuum pressure in the main housing decreases and vacuum efficiency is reduced.
It is an object of the present invention to provide a bag for an upright vacuum cleaner which provides increased vacuuming efficiency and which has a longer useful life than conventional bags.
Another object of the invention is the provision of an oscillating means within the bag which provides selfcleaning of the bag walls to reduce the restriction of air flow normally associated with plugging.
Another object of the invention is the provision of an oscillator tube within the vacuum bag which acts to disperse the vacuumed dirt in a more random pattern to reduce abrasion which normally occurs on the bag interior side walls.
Another object of the invention is to provide such a bag which is simple in design and economical to manufacture and which does not utilize mechanical moving parts which would require maintenance.